This is a proposal from a new and early stage investigator that will evaluate the effectiveness of Case Management-Problem Solving Therapy (CM-PST) and Self-Guided Problem Solving Therapy (SG-PST) for depressed older adults living in a rural community. PST is a behavioral treatment for late life depression proven effective in urban settings with ambulatory and medically ill older adults; older adults with executive dysfunctions; and low-income older adults with a disability when combined with clinical case management (CM-PST) through the CARE-D project (PI: Arean; MH075900). Furthermore, PST and CM-PST have been shown to improve functioning, and may improve self-efficacy and resiliency in depressed older adults, thereby decreasing their risk of institutionalization. Neither PST nor CM-PST has been studied in depressed older adults living in rural settings. Implementing CM-PST in a rural community will likely be challenged by a lack of mental health clinicians, and the fragmented state of rural mental health care systems. A potentially low-cost way to overcome these barriers is to use Senior Peer Counselors to support participant's use of self- guided PST (SG-PST). The main objectives are to examine the clinical effectiveness of CM-PST in reducing depressive symptoms and improving functional ability of older adults in a rural community; compare outcomes in a rural community to those in an urban community (data from the proposed and CARE-D projects); examine the relative effectiveness of CM-PST and SG-PST interventions in a rural community; and explore the feasibility of implementing CM-PST and SG-PST in a rural community through a process evaluation. Geographic Clinical Aims (rural vs. urban): 1. Evaluate effect of CM-PST on depressive symptoms (HDRS) in rural older adults suffering from major depression. 2. Evaluate effect of CM-PST on functional ability (WHODAS) in rural older adults suffering from major depression. 3. Determine if depression and functional effects in rural settings (year 5 outcomes from proposed project) are non-inferior to effects in urban settings (CARE-D project). Translational Clinical Aims (CM-PST vs. SG-PST): 4. Among rural-dwelling older adults, determine if depression and functional outcomes of the SG-PST intervention are non-inferior to outcomes of the CM-PST intervention. Translational Implementation Aims (CM-PST vs. SG-PST): 5. Evaluate acceptability (refusal rate, dropout rate, satisfaction), barriers (collected from participant exit surveys and implementation process interviews), fidelity to the intervention models (CM-PSTAS, CMAS), and cost (direct services budget per participant) of implementing CM-PST and SG-PST in a rural setting.